The correct answer is D.
From the scientific research conducted so far, we know that in the early Earth's history the atmosphere lacked oxygen and was mostly filled with other gases like methane. The increase in oxygen levels happened when the plants started producing oxygen as a byproduct of the process of photosynthesis.
The research so far also shows that the RNA was present before the DNA and that the microspheres might have been essential to the development of life on Earth.
A twitch is defined as a single, brief contraction period and then relaxation period of a skeletal muscle in response to a single stimulation. Contraction period involves receptive power strokes that pull the thin filaments past the thick filaments shortening sacromeres and muscle tension increases as the sacromeres shorten. Relaxation period begins with or release of cross bridges resulting from the return of Ca2+ back to sarcoplasmic reticulum. The strength of skeletal muscle contractions can be broadly separated into twitch, summation, and tetanus. A twitch is a single contraction and relaxation cycle produced by an action potential within the muscle fiber itself.
A. Gas can cause a lot of damage and that’s why you have to be careful around it
